Discussions

So I have been struggling with 2 issues with my APM on an X8.

1. After recently resetting to defaults and starting over, the APM will not remember my radio calibration. Regardless of how many times I try, it says it has completed but when I try to arm it says radio not calibrated. The only way I can fly is if I disabled pre-arm checks. FYI I am using PPM.

2. My trim constantly changes. I will take off and fly and it seems ok but eventually starts to drift forward more and more. I can trim it (it uses a lot of trim) to get it stable but the next flight I may have to take all the trim out. I have tried the auto-trim, save trim etc and have the same problem. I have reset all trims and am just using the trims on my radio now. I am not talking about a slight drift, I can actually see the tilt in the frame. On my ahi (osd and MP) you can see that it appears to be working correctly. When it is leaning forward, the AHI indicates it. It is almost like the APM knows it is tilted but won't apply the correction or it thinks I am pushing forward on the stick.

Troubleshooting done;

Reloaded firmware

Recalibrated ACC many times

Reset level in CLI many times. Even if I intentionally set level with the nose up, it still does the same thing.

ESCs calibrated

I have installed ublox GPS/Compass and it didn't make a difference.

Tried shimming the APM, no difference.

Tried mounting the APM backwards and specified that it was 180 degrees offset. No difference.

Frame is balanced and arms are in the same plane. Motors are level.

Again, the APM seems to know it is tilted according to the AHI, but it isn't making the corrections.

I will mess with this a bit more but am about to pull it out and go with a different controller.

Specs;

APM 2.0 with latest firmware available in the latest MP.

UBLOX GPS/Compass

3DR MP Power Module

I have a recent log file if it would help.

Thanks